calculus i review

Newton’s method

Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025

Definition

Newton's Method is an iterative numerical technique used to approximate the roots of a real-valued function. It involves using the derivative of the function to iteratively converge on a root starting from an initial guess.

5 Must Know Facts For Your Next Test

  1. Newton’s Method requires an initial guess, and its accuracy depends heavily on this choice.
  2. The formula for Newton's Method is $x_{n+1} = x_n - \frac{f(x_n)}{f'(x_n)}$.
  3. Convergence is typically quadratic if the method converges, meaning errors decrease exponentially with each iteration.
  4. If the derivative $f'(x)$ is zero or close to zero, Newton’s Method may fail or provide inaccurate results.
  5. Newton's Method can diverge if the initial guess is not sufficiently close to the actual root.

Review Questions

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